genetic variation + manx cats Flashcards
to not fail
Adaptations
Traits/Phenotypes which allow an organism to better survive in its environment
Allele
Alternate version of a gene
Amino acids
The building blocks of proteins
Ancestor
An organism (or species) from which other organism (or species) have evolved
Antiparallel
The two strands of a DNA molecule run in opposite directions
Asexual reproduction
Requires only one parent. All offspring are genetically identical to the parent
Bases
Adenine, cytosine, guanine, thymine
Chromosome
A long strand of DNA containing a specific set of genetic information
Complementary base pairs
A-T and G-C. Ensures the genetic code is replicated correctly during DNA replication
Crossing-over
Swapping of DNA between homologous chromosomes during the meiosis process. Increases genetic variation
Deoxyribonucleic acid
A molecule that carries the genetic code
DNA sequencing
The process of finding out the exact order of bases on a length of DNA
Dominant
An allele that is always expressed when it is present. Represented using capital letters. E.g. BB, Bb
Evolution
Gradual change in the genetic code of organisms over a long period of time. May result in the formation of a new species
Fertilisation
The process where the DNA from an egg and sperm fuse together
Gametes
Sex cells containing half the chromosomes of the parent
Genome
All the DNA in a single cell of an organism
Gene
A short segment of DNA that codes for a particular protein/phenotype
Genetic code
The bases of a gene are read in sets of three and each triplet codes for an amino acid, which in turn are joined to make a protein
Gene marker
A short segment of DNA that can be used to follow inheritance of a trait (especially if it is not visible) or determine relatedness of different organisms.
Genetic variation
The total number of different alleles in a population of organisms.
Genotype
The combination of alleles for a gene. E.g. BB, Bb, bb
Genotypic ratio
The predicted ratio of inheritance of alleles from the mating of two individuals
Heterozygous
Two different alleles in a genotype. E.g. Bb
Homologous pairs of chromosomes
Two chromosomes in a cell with the same genes on them. One chromosomes is inherited from each parent.
Homozygous
Two alleles in a genotype are the same. E.g. BB or bb
Independent segregation
Homologous pairs of chromosomes line up at random and independently assort with other homologous chromosomes during the process of meiosis.
Karyotype
A picture of all the chromosomes in a cell, ordered from largest to smallest in homologous pairs.